[Asterisk-Users] Will Echo problems EVER be solved, I'm scare d

[Colin Anderson]

dude it's gotta be something with your system. Im using same setup at home
with a TDM22 with no probs. Asterisk at Home 1.5, Compaq Deskpro EN P3 500,
cordless phones.  You did a ton more than I did, I basically plugged
everything in and installed a at h.Worked first try. 

Hate to say it, but would it be possible to try a different system? Even an
old system as long as it is PCI 2.2.

The big clue here is that you say that echo is the same regardless of phone
or PSTN source. That pretty much narrows it down to the system. What's your
score on /usr/src/zaptel/zttest?

This is the burn of Asterisk. It's extremely difficult to make random
hardware work good with it. Because it is designed for commodity hardware,
stability is a moving target. Even bios revs can make a difference. In the
deployment I have done for my work I have a master Asterisk server and 30
IAX servers in remote locations. All 30 boxen are exactly the same, down to
the BIOS rev, Linux version, network cards, everything. This is the way to
do it, to narrow down infinite variables to a controllable few.  You need
patience or luck but preferably both. You have an advantage, though. From
your post it looks like you've done your homework, you aren't a dumbass, and
you know how to arrive at a conclusion through process of elimination.
You're on the right track. Don't give up now, 'cause you are close.

> ----------
> From: 	canuck15
> Reply To: 	Asterisk Users Mailing List - Non-Commercial Discussion
> Sent: 	Wednesday, August 24, 2005 5:02 PM
> To: 	'Asterisk Users Mailing List - Non-Commercial Discussion'
> Subject: 	RE: [Asterisk-Users] Will Echo problems EVER be solved, I'm
> scared
> 
> <<File: ATT11994.txt>> 
> Wiley,
>  
> The very first thing I checked was for IRQ problems.  I apoligize for
> forgetting to mention that.
>  
> The only thing I found in the Google search you suggested is a thread from
> January 2004 suggesting that businesses should ONLY use a T1 card with a
> channel bank instead of X100P cards.  I understand the "don't use X100P"
> part but I just assumed the TDM400P with echo cancellation is working fine
> now.
>  
> I am using a WRT54G (switch).  I am NOT connecting via wireless.  I have
> no traffic to QoS.  Just VoIP and a WRT54G switch is quite capable of that
> as far as I know.  No hubs!
>  
> I pretty much just use AAH now for it's ease of install but I have rolled
> my own in the past.  The echo has persisted through AAH v1.3, 1.4, 1.5.  I
> have recently (yesterday) installed the latest Asterisk and Zaptel CVS
> head development tree just to see if it made a difference and it DID NOT!
>  
>  
>  
>  
> 
>   _____  
> 
> From: Wiley Siler [mailto:wsiler at education2020.com] 
> Sent: Wednesday, August 24, 2005 2:00 PM
> To: Asterisk Users Mailing List - Non-Commercial Discussion
> Subject: RE: [Asterisk-Users] Will Echo problems EVER be solved, I'm
> scared
> 
> 
> Just because you cannot get it to work does not mean that IT does not
> work.  
>  
> Just using the right motherboard is not enough.  Did you check for IRQ
> problems?  You don't mention whether you have checked for this.
> Look for a thread called "Asterisk-Users Small office setupusing analog
> lines w Asterisk" in the archive via Google.
> use site:lists.digium.com
> Try all the things listed in that thread.
>  
> Do you have a network that is capable of VoIP?  Are you using hubs when
> you should be using switches?
> There is a major difference and hubs WILL NOT work reliably with VoIP. 
> Are you using QoS on your switches if you have lots of network traffic?
>  
> If you are using your own Distro and installing from scratch, try to use
> Asterisk at Home just to see if you still have the same problem.
>  
> I am putting my money on an IRQ issue myself.
>  
> W
>  
>  
>  
>  
>  
> 
>   _____  
> 
> From: asterisk-users-bounces at lists.digium.com
> [mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of canuck15
> Sent: Wednesday, August 24, 2005 1:38 PM
> To: asterisk-users at lists.digium.com
> Subject: [Asterisk-Users] Will Echo problems EVER be solved, I'm scared
> 
> 
>  
> I came into this with my eyes wide open.  I have read ABSOLUTELY
> EVERYTHING there is to be found on the net about avoiding echo problems
> BEFORE I even attempted to create a production system.  Since lots of
> people are apparently using this in production environments now I just
> assumed that echo IS avoidable.  
>  
> As others have recommended, I created a test system with the proposed
> production parts.  I bought a couple different SIP phones to try and a
> Digium TDM01B card.  I am using an older PIII 1Ghz system with 815chipset
> (PCI Rev2.2) with 256MB for my test system.  The only thing that will be
> different on a production system is that I will be using a newer chipset
> PC with faster processor and 512MB.  Probably Intel 7505, 7210, or 7211
> chipsets which seem to be the most compatible with Asterisk.  
>  
> My problem is that I cannot eliminate echo no matter what I try.  I
> seriously doubt that a newer chipset faster PC with more memory will
> eliminate or even reduce my echo problems based on what I have read.   I
> am not about to drop more cash to try and find out.  Essentially, my
> findings are that Asterisk is NOT production capable for my configuration
> which is via FXO and PSTN.  That is probably THE most common configuration
> so if it is not production capable like that it isn't production capable
> period as far as I'm concerned.  What a disappointment :(.  
>  
> Unless I am missing something I am sure that many many people with a
> similar configuration in a production environment have the same problem.
> Perhaps they are just living with it??  For me it is just as unacceptable
> on an Asterisk system as it is on a traditional PBX.  Some calls are ok
> and some are not.  No correlation to local, long distance, time of day.
> There always seems to be some echo.  Sometimes it is worse than other
> times.  Again, no correlation to local, long distance, time of day.  Tried
> connecting to ATA adapter and using VoIP provider instead to see if the
> telco was causing the problem.  That did not change anything.  Still the
> same general echo problem
>  
> The things I have tried include in no particular order and not limited to
> are:
>  
> *Buy latest TDM400P with latest FXO module
> *Ensure copper connection to analog telco lines and telco are not causing
> problems including running a separate shielded line to the demarc AND
> having the telco guy come out and test the levels, impedance etc.
> *Adjust RX/TX levels as per Asterisk Wiki using the quick Ztmonitor method
> and by using the detailed Ztmonitor method via a Telco 102milliwatt test
> phone #.  The end result was RX=8.0, TX=-1.0.  Since I still have echo
> problems I have tried all sort of other settings without success.
> *After ALL of the above, try every possible combination of all of the
> following on Asterisk v1.0.9: echocancel (off, on, 128, 256, 16, 32, 64),
> echowhenbridged (on, off), echotraining (off, on, 800), Mark 2 (default,
> aggressive, CVS head developments, bugs.digium.com patches, adjust
> threshold level as per wiki etc. etc.)
> *Make sure echotraining line is before FXO channel assignment in
> zapata.conf file
> *Run fxotune which did not find a need to adjust the FXO levels
> (1=0,0,0,0,0,0,0,0)
>  
> Based on all the above testing the best settings were pretty much in line
> with what most people are finding. 
> echocancel=on. echowhenbridged=on, echotraining=800, Mark 2 echo
> canceller, aggressive cancellation OFF, bugs.digium.com #2820 patch,
> RX=8.0, TX=-1.0.
>  
> Still have echo.  Aggressive mode helps a bit but then the other persons
> voice get's cut off a lot especially when I talk and the cutting in and
> out of the canceller is more noticeable and objectionable in general than
> if Aggressive is turned off.
>  
> I have two SIP phones.  An Aastra 9133i and a Grandstream GXP2000.  Echo
> problem is the same on both phones. 
>  
>  
> I am located within a metropolitan area in Canada.
>  
> Any comments and/or suggestions would be greatly appreciated as I am
> pretty much out of ideas and ready to give up on Asterisk as a suitable
> traditional small business phone system replacement.
>   
>